Question

HELPP!!!


You mother and father took turns driving on a
640-mile trip that took 11 hours to complete.
Your mother drove at a constant speed of
55 mph and your father drove at a constant
speed of 60 mph.
a) How long did your mother drove

(i tried doing cross multiply and divide but that didnt work ?)

Answer 1

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Answer 2

m- Hours mother drove the car and f - no. of hours father drove the car. Then acc. to ques.
m+f = 11
and 55*m + 60*f = 640 (Total distance traveled)
55*m + 60*(11-m) = 640
55m + 660 - 60m = 640
5m= 660-640
5m = 20
m = 4.
I hope it helps !!

Answer 3

thank you